What is marketing exactly?

[million$gon]

fits together with graphic design like pancakes and pure maple syrup !

Marketing is a bunch of things that point towards the same ultimate goal, to bring supply and demand together, and/or to improve the level of demand so people will buy products or services that companies create. Increasing the demand is technically an economics thing, which means people will be willing to pay more instead of less for the same product/service. Increasing quantity-demanded means more people will buy, or people will buy more amounts or buy more often, of the product/service. Marketing helps people become aware that a certain company's products exist, and the qualities of their product/service. Marketing helps people decide to buy something if they realize that, actually, ya, they want it. Marketing can also help people to want some product/service.

Graphic design helps people see a product/service offer, and helps them to feel like they want it or need it.

If you take courses, you will get into the details, which include the famous bunch of "P"'s :
Product, Price, Promotion, Packaging, Presentation, etc...
Price will be something that helps you decide how to present something, and all the other P's often do involve graphic design a lot.